What are your thought on SS technology

[Brian Ashton]

Hi Brian,

Not to be argumentative, but I wanted to say a couple of things in regard to your statement:

"One thing that is 100% assured- all the parts in those saws will fail regardless of how they're treated."

This is true in the same sense as "the sun will blow up in a billion years, so everything will eventually fail." It may be true, but it's not particularly helpful.

What is the failure rate of, say, a bolt that is used within specification of the machine's design envelope? (Forget about alloys, grades, etc. for now to simplify) The failure rate odds are in the one to 10,000,000 range, and that's being very conservative - in other words not in your lifetime, or your grandchildren's lifetime. (How much extra are you willing to spend on a saw that lasts past your grandchildren?) This argument then extends to all of the parts of the saw. Lets say we design for 3 generations, a hundred years. We do have to state what is typical usage, extraordinary usage, and what is not allowed. Perhaps cutting through a few nails in its lifetime is allowed, cutting aluminum with it perhaps, but surviving a direct lightning strike is not.

As someone who has an aviation system safety science background (this is the study of calculating reliability and failure modes of aviation related systems), I have a modest bit of insight into reliability of both mechanical systems and electronic ones, and the quote above, while very commonly spoken, just doesn't reflect what we now know to be true about reliability.

However, your point about parts becoming scarce due to obsolescence is a good one, but I wouldn't worry about the DB9 - it is used in so many Mil Spec devices that government contracts (which are very hard to kill) will require those things to made way past a better connector becomes widespread! I would worry more about the availability of some of the more esoteric electronic components. Unfortunately, the only guy who can speak to this is the design engineer who designed the SS circuits, and the rationale he used for selecting the parts. Hopefully, widespread availability of parts was an important goal for him. Most of the time it is certainly in the company's best interest to use widely available parts, as well as the consumer's.

I doubt that anyone had a System Hazard Analysis or a Failure Effects Mode Analysis done for the saw, but then again these aren't cheap and would probably raise the cost of the saw considerably, and the argument that most customers wouldn't really be interested in the result and therefore not be willing to pay for the additional development cost is a real issue. A measure of certainty about the reliability of a system is not cheap.

Adding any components to a system always lowers the reliability somewhat, so it stands to reason that two otherwise identical saws, one with the SS mechanism in place, and the other without, the more complicated one would have a higher failure rate. However, how much higher is proportional to whether or not the added complexity is prone to failure itself. All it has to be is out of the range of your grandchildren, which isn't too hard to do.

Like everything else, it just boils down to how experienced the engineer was who designed it, and whether he was given the time and resources to do a good job.

May have been a bit general when I said everything will eventually fail... But! What sets this saw apart is that the parts aren't readily available (relatively speaking). So when I put a SS next to a Powermatic I have to ask the question. When something fails, which is going to give me the least amount of stress to get it up and running again? To me I'd have to say the Powermatic. The safety feature is obviously an excellent bonus but which is more likely: I loose a finger or the saw at some point has a break down. For me I'd say the saw will fail first. So that's why I ask such questions. Also I don't buy things simply to sell them later. I plan on having most of what i buy, such as tools, for the rest of my life... So again which do I think will still be around in 25 years? Powermatic? definitely - even if the company goes extinct I'll be able to keep it running as has been the case for most any machine of similar pedigree over the last 100 years... SS? I doubt it. At this point, I personally don't think you'll see too many that are 20 years old that haven't bypassed the safety feature or have spent a lot of coin on upgrades.

I guess to sum it up it would be good to see a standard developed that allows some sort of lateral movement in choice of fixing a dead machine, other than completely ripping our the system that made you buy the saw in the first place... If my oneway inverter dies I don't need to buy another Yaskawa drive (in fact I couldn't even if I wanted to, as Yaskawa are next to impossible to find in australia. I might have the only oneway in the southern hemisphere to be honest...). But I can plug in any inverter and be up and running right away. Oneway were somewhat "exotic" when they first came out but the parts were readily available through multiple channels - you weren't reliant on them alone for anything that had a high probability of future failure. You can't say that for the SS. That always makes me take a wait and see approach to a product.

[Will Overton]

I do think that anything that uses cutting edge electronics will be improved upon a lot faster than an all mechanical products. I also know people who put off buying a computer because something better would be out in a year. At some point, if it's something you want, you either jump in or stand on the sidelines.

As an example, my first quality cameras lasted 20 years. The pictures quality got better over the years because of improvement in film. I held on to my first good ($5000) digital camera for almost 5 years. But new technology dictated that the only way to get the latest improvements in picture quality, was to get a new camera. It's coming up on 5 years, and I see a new camera in my future.

My guess (hope) with SawStop, is that if there is a large enough user base, that even if the company goes under, a third party manufacturer will see a market for replacement parts.

[Ryan Hellmer]

I like all the debate on the SS and I'm hoping to get a PCS soon. I wonder what merit there is to the technology obselesence though. While to us woodworkers this is a phenomenal jump in technology, but the sensors and hardware are not particularly earth shattering. I liked the comment about the engineering. These are relatively simple circuits and semiconductors, very-likely off-the-shelf. The only thing novel or "patentable" about the technology is the arrangement of these simple devices. I think SS is here to stay, I think that the braking mechanisms will either be licensed or stolen and applied to everything manufactured by our neighbors in the far east. Look at how prior tool technologies were copied, the old unisaw trunion system showed up on EVERYTHING, the DJ-20, contractor saws, the jet clone cast iron frame bandsaws there are many brands and sometimes they all just have different coats of paint. If the past is any indicator there will not be a single source and finding parts won't be that hard. And for all you that tout the availability of parts, have you ever tried to order parts from most of these suppliers, even PM doesn't support the 63 anymore, but you can buy clone parts from grizzly from the G1022 tablesaw that fit perfectly. Just my rant for the morning.

Ryan

[Kyle Iwamoto]

May have been a bit general when I said everything will eventually fail... But! What sets this saw apart is that the parts aren't readily available (relatively speaking).

What are you talking about? My local Woodcraft has common parts for the SS. I have a pair of brakes for replacement. I got a replacement guard. (I took the pawls off one to prevent scratching) Just as easy to get an insert for the SS as it is for my PM band saw. I think you're inventing things that you want to come true.